A typical mascara applicator comprises a threaded handle, a stem and an applicator head. A common container of mascara has a threaded neck that leads into a cylindrical reservoir of product. A wiper is located in the neck, and has a lower orifice that is designed to wipe the stem and applicator head as they pass through the wiper. As the handle is screwed onto the neck of the container, the stem rotates around the central longitudinal axis of the wiper. As a result of this, the wiper orifice is able to tightly hug the perimeter of the stem for efficient wiping. If the stem was not coaxial with wiper, then the wiper orifice would have to be large enough to accommodate the orbit of the stem. In that case, the orifice would not hug the perimeter of the stem, and the wiping function would be compromised.
A tweezers is a pair of levers that have proximal ends that articulate with each other (either directly or through an intermediate member) and distal ends that remain free. The articulation acts as a fulcrum, and is such that an internal tension is stored in the articulation that tends to push the levers toward a rest position. When pressure is externally applied to the levers between their proximal and distal ends, the levers move between the rest position and a second position. The rest position corresponds to no applied pressure. In the simplest form of tweezers, the rest position means that the distal ends of the levers are spaced apart, and application of external pressure brings them closer together to effect a pincer grip. The articulation may be effected by welding or unitary construction or any type of joint that can hold and release tension as just described.
Various tweezer type cosmetic applicators are known, but we are only interested in immersion type tweezer applicators that descend into a reservoir of product as the closure is being seated onto the container.
U.S. Pat. No. 5,611,361 discloses a mascara applicator-container system in which the applicator comprises a handle, one end of a stem rigidly connected to and extending from the handle, and two applicator heads extending from the other end of the stem. The applicator heads and stem may be immersed in a container of product, and the handle may be threaded onto the neck of the container. As the handle is threaded onto the neck, the applicator heads revolve around the axis of the container neck. There are no wipers in the neck or container, nor anything else to interfere with the revolution of the applicator heads. The system suffers from not having wipers to remove excess product and clumps from the applicator heads, a feature that is often considered essential for good results. Also, the multiple applicator heads are not really intended to be used in a tweezer fashion.
U.S. Pat. No. 6,325,071 discloses a tweezer type applicator system for mascara. The system has a dual bladed mascara applicator which is received in a cylindrical product container. A wiper has a disc shape with two apertures to accept the applicator blades. A wiper housing receives the wiper and is rotatable in the product container. As with the simplest type of tweezers, pressure is applied near the middle of the blades. In order to keep the middle of the blades from getting dirty with product, the level of product in the container and the placement of the wiper in the container, is relatively low, well below the orifice of the container. According to the patent, only about one third of the container can be filled with product, which is well below conventional mascara fill levels. Because of this, the container must be fashioned with a custom lip on its inner wall, to give the wiper housing something against which to rest, to prevent unwanted vertical movement of the wiper. Of course, the low product fill level is a great waste of container space compared to conventional mascara applicator systems. Also, in this and other cosmetic tweezer applicators, it is necessary to apply pressure to the tweezers to effect a pincer grip while making up the eyelashes or hair. Maintaining even pressure for an extended period while manipulating the tweezers may be difficult, and may have an adverse effect on the application. Also, this tweezers cannot be operated while in the container.